1. Field of the Invention
The invention relates to a board for gliding on snow or ice, and especially a snowboard.
2. Discussion of Background and Material Information
Such a board is intended to support both of a skier's boots, which are retained, side by side, by binding elements. Generally, the two boots are offset along the median longitudinal axis of the board, and they are oriented with respect to this axis along an angle varying approximately between 5 and 90 degrees from one side or the other of the longitudinal axis. Usually, this axis is adjustable. Such a gliding apparatus is, for example, described in U.S. Pat. No. 3,900,204.
The invention more specifically pertains to the structure of the gliding board.
It is currently known to produce such boards by implementing construction techniques originating from the conventional ski. Thus, there are snowboards constructed according to a sandwich or box structure.
However, during the glide, the snowboard operates differently from a conventional ski in view of forces imposed on it. Indeed, both of the surfer's boots are retained on the board; in addition, they are retained asymmetrically with respect to the board. Generally, during the glide, the board is subjected to forces greater than those of a normal ski. The surfer has two support points on the board, and, by a differential action of both boots, the surfer acts on the flexion or torsion of his or her board. Finally, the surfer has an asymmetrical position with respect to the board and with respect to the slope. The two lateral edges of the board are not similarly biased.
The flexion and torsion of the board are parameters which influence the maneuverability or operational qualities of the snowboard, as well as the geometrical shapes of the board, mainly length, width and shape of the side cuts.
The weight and general resistance of the board are also parameters which determine the quality of the snowboard.
For a conventionally constructed board, it is very difficult to master each of these parameters in order to obtain the required gliding, maneuverability or operational qualities. Indeed, these parameters are mutually connected, such that the variation of one parameter indirectly modifies the other parameters of the board. Most often, a compromise is adopted.